This invention relates generally to a device for mounting a workpiece upon a support surface and, more particularly, to a magnetically held mounting support for a light fixture or the like object.
A magnetic mounting support for a light fixture of the type illustrated in copending U.S. Patent application, Ser. No. 37,365, filed May 9, 1979, and assigned to the same assignee as the subject invention, includes a support shaft upon which a light fixture is received and a magnetic base joined to the support shaft. The support shaft includes a threaded end which is received in an aperture defined in the magnetic base. The support shaft includes an enlarged stop formed thereon to limit the insertion of the threaded end of the shaft into the base. A flat metallic washer and nut is received on the threaded end of the shaft and the nut is tightened down to secure the base and shaft in a joined condition.
The magnetic base is used frequently to attach the support to the underside of a metallic shelf with the support shaft suspended from the base. A light fixture is received on the support shaft and is mounted thereon over a table, desk, or similar surface for illumination thereof.
While the aforementioned magnetic mounting support is, for the most part, effective in mounting a light fixture on the underside of a metallic shelf or other metallic support surfaces, as described, the mounting support suffers one drawback. In certain instances, if a relatively heavy item is dropped or placed forcibly onto the upper side of the shelf on which the mounting support is magnetically held, the magnetic base will be jarred free, causing the light fixture or other objects suspended from the mounting support to drop with the mounting support to the table surface below. Such an occurrence is infrequent, but if it should happen, could cause damage to the light fixture or possibly to objects placed on the surface below the shelf.